Microleakage and sealant penetration in contaminated carious fissures

Objectives

The aim of the present in vitro study was to evaluate the effect of an adhesive system on microleakage and sealant penetration depth in carious fissures after different surface contamination circumstances.

Methods

Extracted third molars (n = 128) with small occlusal cavitated carious lesions were randomly divided into eight experimental groups and sealed under four different surface conditions. 1, Dry conditions; 2, water contamination; 3, saliva contamination; 4, saliva contamination and air-drying. Two sealant protocols were applied, one using a fissure sealant (Teethmate F) and one using an additional adhesive system (SA primer and Photo Bond). The control group consisted of sound third molars (n = 16), that were sealed under dry conditions. After thermocycling (n = 500 cycles), teeth were immersed in 1% methylene blue for 24 h, sectioned and digitally photographed. Microleakage was evaluated on a three-point rating scale and analysed using a Chi-square test. Additionally, the presence of caries and incomplete sealant penetration was scored from photographs and analysed using logistic regression.

Results

A statistical significant difference regarding microleakage scores was present between sealed carious and sealed sound fissures. The use of an adhesive system in case of water contamination significantly reduced microleakage (p < 0.05). With regard to sealant penetration depth, there were significant differences present for carious sealed fissures, use of an adhesive system prior to sealing, and water and saliva contamination.

Conclusions

Use of an adhesive system improved the effectiveness of sealants placed after water contamination in carious fissures. However, sound fissures showed less microleakage and better penetration abilities than carious fissures.     

Retention and penetration of a conventional resin-based sealant and a photochromatic flowable composite resin placed on occlusal pits and fissures

This study compares the retention and penetration of a conventional resin-based sealant (Fluroshield) and a photochromatic flowable composite resin (Tetric Flow Chroma) placed on occlusal pits and fissures and submitted to thermal or chemical cycling regimens. Penetration assessment--ten premolars were sealed with each material, isolated (except for the sealed surface) and immersed in 0.2% Rhodamine B. The teeth were serially sectioned in a mesiodistal direction. The images of the sections were digitized and analyzed (ImageLab). The distance between the most superficial and the deepest points on the occlusal central groove was calculated to determine the groove's total depth. The length of the central groove filled with the sealant was divided by its total depth to obtain the percentage of sealing of the occlusal groove. Retention assessment--30 premolars were sealed, their occlusal surfaces were photographed and the area occupied by the sealing materials was demarcated (ImageLab). The teeth were submitted to different treatments: thermocycled, stored in artificial saliva and immersed in acetic acid and saliva (10 cycles/day protocol for 30 days). New photographs were taken to assess the final area occupied by the materials. The difference between the final and initial area was calculated to obtain the material loss. The data was analyzed (two-way ANOVA and Tukey's test P<0.05). Both materials presented similar penetration of the occlusal central groove. After thermal and chemical cycling, the materials did not differ with respect to retention, except for immersion in acetic acid. In this case, Tetric Flow Chroma presented greater retention than Fluoroshield.     

Reproducibility of DIAGNOdent 2095 and DIAGNOdent Pen measurements: results from an in vitro study on occlusal sites

The aim of this in vitro study was to investigate the intra- and interdevice reproducibility of the DIAGNOdent 2095 (DD2095) and the new DIAGNOdent Pen (DDPen) on non-cavitated occlusal caries sites. Altogether, 241 sites on 90 molars were inspected twice with both devices and by four examiners. The intra/interdevice reproducibilities were assessed by means of the intraclass correlation coefficient (ICC) as well as by the range of the 95% limits of agreement of Bland & Altman. Additionally, a linear mixed-effects model was fitted with fixed effects for the visual scores and the devices used and random effects for occlusal sites and examiners within each measurement site. In result, the following values were determined for the intradevice reproducibility: DD2095: ICC 0.89, range 42.3; and DDPen: ICC 0.88, range 49.3. The interdevice reproducibility was found to be in the same order of magnitude (ICC 0.82, range 53.7). The comparison between both devices indicated significantly lower mean values for the DDPen. The estimates of the linear model show that there is a high variation between the sites that cannot be explained by the fixed effects. In conclusion, both devices showed an imperfect reproducibility, which indicate the usage as adjunct tool only in clinical practice.     

Influence of tooth-polishing pastes and sealants on DIAGNOdent values.

OBJECTIVE: The purpose of this study was to investigate the influence of tooth-polishing pastes and sealants on values obtained with a caries diagnostic system based on detection of caries-associated fluorescence (DIAGNOdent, KaVo). METHOD AND MATERIALS: Ten tooth-polishing pastes and four dentifrices were measured alone, and it was shown that products containing pumice gave high DIAGNOdent values. The deepest occlusal pits of 20 extracted sound premolars (12 unsealed teeth, 8 sealed teeth) were measured before polishing, after rotating-brush polishing with pumice-containing tooth-polishing paste, and after final rotating-brush polishing with water in this in vitro study. In the clinical phase, the deepest occlusal pits of 21 molars and 2 premolars that clinically required application of sealant were measured before polishing, after rotating-brush polishing with one of two pumice-containing tooth-polishing pastes, and after sealant application. All measurements were done five times, and the average values were obtained. Data were statistically analyzed using analysis of variance subsequent to Fisher's protected, least significant difference. RESULTS: Clinical study showed that the value after polishing with either of the two polishing pastes was significantly higher than the value before polishing. Both in vitro and clinical studies showed that the value was increased by pumice-containing paste polishing and rotating-brush polishing with water after paste polishing could not recover the value to the level before paste polishing. Sealant treatment in the clinical study significantly decreased DIAGNOdent values, and the values after sealant application were lower than the values before polishing. CONCLUSION: Polishing pastes and sealants used in this study could interfere with DIAGNOdent values.     

A plaque index for occlusal surfaces and fissures

Abstract. Plaque indices have largely been developed for buccal and lingual tooth surfaces. There has been minimal interest in plaque accumulation on occlusal surfaces despite the predilection for caries at these sites. A numerical plaque index (0–5) is described based on the presence and distribution of plaque in the fissures and over the occlusal surfaces of permanent molar and premolar teeth. The repeatability of a single examiner in scoring the index was performed using 4 groups of 10 subjects. Each group of volunteers suspended tooth cleaning for 48 h and the index scored after disclosing plaque deposits. The index was rescored 60–90 min later. Plaque area was also determined by drawing the outline of plaque onto grids. Except for one condition of repeatability for one group, the 4 conditions of repeatability in scoring the index were met for all 4 groups of subjects. The sensitivity of the index and area recordings to detect plaque removed by brushing was then evaluated. A group of 10 subjects had plaque scored by index and area after suspending toothcleaning for 48 h. Subjects were then randomly allocated to brush or not brush their teeth and plaque rescored. The experiment was then repeated and brushing or not brushing crossed over. Highly significant differences between brushing and no brushing plaque indices and areas were determined. In conclusion, the occlusal fissure plaque index was easy to apply, repeat-able and sufficiently sensitive to detect plaque removed by brushing. The index could find use as an additional measure of oral hygiene, in clinical trials on plaque control and possibly epidemiological studies relating to caries.     

Relationship between occlusal interference and hearing ability

Clicking sounds are one of the symptoms that appear in the temporomandibular joint dysfunction at a high rate. But they are sometimes found in healthy subjects also, so that clicking sounds are seldom recognized as an pathologic condition. Study reports on clicking sounds in the past concentrated mainly on their cause, process of their appearance and their spectral properties. These studies were, however, all based on the understanding that clicking sounds were a kind of symptom or signals that accompanied the unbalanced jaw relationship. They did not examine pathologic conditions or functional change caused by the very existence of clicking sounds. This author has been reporting on the influence of clicking sounds on hearing abilities. This time the author considered it necessary to study the cause for rise of the hearing level of the clicking subjects in relation to the unbalanced positions of their jaws. The author therefore examined the relationship between the phases of occlusal contact and hearing abilities of the clicking subjects. From the results, we obtained the following conclusions: 1. As for the frequency of appearance of clicking sounds, 28 out of the 175 healthy subjects (aged either 21 or 22) had clicking sounds on one side, accounting for 16.0%, at the hazard rate of 1%. There was no differences between the sexes and between the right and left sides. 2. Of the 37 subjects, the cases in which the centric position fall on the intercuspal position were only three among the 17 non-clicking subjects (Group I), accounting for 17.6% and none, among the 20 clicking subjects.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of alteration in organic material of the occlusal caries on DIAGNOdent readings

DIAGNOdent is a laser fluorescence device used for dental caries diagnosis in occlusal and smooth surfaces. Despite the promising preliminary results, the molecules involved in the increase of fluorescence in carious lesions remain unclear. The aim of this study was to compare the laser fluorescence readings before and after changes in the organic material of occlusal carious lesions in primary teeth. Twenty-four primary molars stored in saline solution with at least one site with occlusal caries were divided into two groups. The control group had 17 sites with caries and the experimental one had 16 sites. The carious lesions were measured with laser fluorescence. The experimental samples were then removed from the storage solution and immersed in a 2% sodium hypochlorite solution for 24 hours. After washing with water, the teeth were measured again with the laser fluorescence device. The teeth of the control group were submitted to the same procedures, but saline solution was used instead of the sodium hypochlorite solution. A statistically significant reduction in the mean of the readings after immersion in the two tested solutions compared with the initial readings was observed in both groups, but the decrease was statistically higher in the experimental group (p < 0.0001). In this study, the data indicate that changes in the fluorescence of carious lesions measured by the laser fluorescence are mainly due to the organic content alterations rather than to the mineral loss.     

Penetration of acid solution and gel in occlusal fissures

This study evaluates the penetration of an acid solution and two gels with different viscosities into occlusal fissures. Morphologically distinguishable differences in enamel at the occlusal site was examined as to whether the tooth is treated by acid solution, low-viscosity acid gel, or high-viscosity acid gel as well as the extent of involvement, using either a conventional or scraping method of application. The study also looks at the use of a gel acid agent in the pit and fissure sealant treatment.     

The intra/inter-examiner reproducibility of the new DIAGNOdent Pen on occlusal sites

OBJECTIVE: This in vitro study on occlusal sites aimed to assess the intra/inter-examiner reproducibility of the new DIAGNOdent Pen (KaVo, Biberach, Germany) and to prove the assumption that its handling is easy to learn by dental students. METHODS: Two hundred and forty-one sites of 90 occlusal non-cavitated molar surfaces were investigated twice by 2 dentists and 2 undergraduate students with the DIAGNOdent Pen according to manufacturer's instructions. Intra/inter-examiner reproducibility was assessed calculating intra-class correlation coefficients (ICCs) and the range of the 95% limits of agreement by Bland and Altman. RESULTS: Intra-examiner reproducibility revealed excellent ICCs (0.84-0.92); but the range amounted to 41.2-59.1, which indicate a wide measuring range. The inter-examiner reproducibility using all measurements had to be proved as excellent (ICC 0.84); the range was found in the same order of magnitude as mentioned above (53.2). When measurements were categorised according to treatment related cut-offs a good inter-examiner reproducibility was detected in the interval of <30 (ICC 0.70); an excellent ICC were registered for the interval >30 (ICC 0.51). For both intervals the range values (<30: range 32.3 and >30: range 67.7) exceeded a deviation limit of +/-20%. Both students tended to measure slightly more precise compared to the dentists. CONCLUSIONS: This study revealed a wide measuring range of DIAGNOdent Pen readings. Since there were no differences between dentists and students it can be used as adjunct tool by undergraduates as well. Nevertheless, based on the registered reproducibility the DIAGNOdent Pen should be used additionally to visual inspection and dental radiographs.     

Human prismless enamel and its influence on sealant penetration

A lower incidence of sealant retention has been noted for deciduous compared to permanent human teeth. The presence of prismless enamel, common in deciduous teeth, may significantly influence resin retention due to its limited porosity and penetrability, following acid-conditioning. Prismless enamel allowed very limited resin penetration compared to prismatic enamel, so that mechanical bonding may be impaired.     

Relationship between occlusal plane determinants and craniofacial structures

A cephalometric study was conducted on 34 complete denture wearers to investigate the relationship between the anatomical structures commonly used to determine the occlusal plane and the facial skeletal shape. The results showed no correlation between the shape of the skeletal face, the gonial angle and the length of the mandible versus the location of the retromolar pad, the occlusal plane and Camper's plane. However, a statistically significant linear correlation (P < 0.0001) was found between the facial skeletal shape designated SN POG and the location of Camper's plane. Cephalometric analysis alone cannot determine the location of the occlusal plane in edentulous patients. Intra-oral structures should also be considered.     

Evaluation of different methods for cleaning and preparing occlusal fissures

The effectiveness of different methods for cleaning and preparing occlusal fissures before placing sealants was evaluated. Extracted mandibular molars received such treatments as brushing, pumicing, bur preparing, and air abrasion before application of fissure sealants. FluroShield fissure sealant was then applied to the occlusal fissures. Specimens were subjected to thermo-cycling and then immersed in a 10% solution of methylene blue, and finally sectioned. The sections were examined and photographed in a stereomicroscope, and the dye penetration was recorded using a scoring system. The results indicated that only the control (brushing with a dry brush) and the pumicing groups demonstrated dye penetration to the base of the sealant. Teeth prepared with the #1/4 round bur and air abrasion demonstrated a better seal in evaluated fissures. For this study, those three groups (occlusal fissures prepared with the #1/4 round bur and two air abrasion methods), demonstrated significantly better sealing (P < 0.01) than the control group and the other groups tested.     

Relationship between bacterial infection and evaluation using a laser fluorescence device, DIAGNOdent

The aim of this in vitro study was to investigate the relationship between bacterial infections in carious dentin when detected by two different methods -- polymerase chain reaction (PCR), and a laser fluorescence device, DIAGNOdent. Dentin was removed every 300 micro m in the direction of the pulp chamber in 10 extracted molars with occlusal dentin caries and 3 extracted sound molars. Dentin surfaces were evaluated using DIAGNOdent, and dentinal tissue samples were removed by using a round bur before and after each removal. Bacterial DNA in the dentinal tissues was detected by PCR, using primers based on the nucleotide sequence of a conserved region of the 16S rDNA, and yielded a PCR product of 466 bp. The rates of bacterial detection increased as the DIAGNOdent values increased. In the 10 specimens, the lowest DIAGNOdent value at which bacteria were detected was 15.6; at DIAGNOdent values below 15.6, no bacteria were detected. The results of a receiver operating characteristic (ROC) curve for the DIAGNOdent values showed that the area under the ROC curve was 0.91. This study clarified the relationship between the DIAGNOdent values of dentin caries and the rates of bacterial detection.     

Relationship between occlusal curvatures and bite force in humans

PurposeIt is clinically believed that humans with a broad and rounded dental arch accompanied by a shallow curve of Spee have good masticatory function. However, the relationship between them has not been elucidated fully. The purpose of this study was to quantitatively examine the relationship between occlusal curvatures and bite force.Materials and methodsBite force was measured and analyzed in 20 young adults with healthy permanent dentition and normal stomatognathic function using a bite force recording system. Study models of the mandibular dental arch were scanned with CCD cameras, and X, Y and Z coordinates of the cusp tips of the molars were recorded. Their occlusal curvatures were analyzed using a three-dimensional measurement system.ResultsBite force showed significant positive correlations (0.52 < R < 0.57) with the radius of the anteroposterior occlusal arc of the molar region and the radii of the translateral occlusal arcs in the second premolar, first molar and second molar regions, and showed significant positive correlation (R = 0.71) with the radius of the occlusal sphere of the molar region.ConclusionsIt was suggested that occlusal curvatures is related with the magnitude of bite force, and that the three dimensional spherical analysis of occlusal curvatures is useful predictor of the masticatory function.     

Microleakage and sealant penetration using a vibrating probe

PURPOSE: To evaluate the effect of a vibrating probe on sealant penetration into pits and fissures. METHODS: Thirty-six extracted human third molars were used. The occlusal surface of each molar was cleaned with a rubber cup and pumice slurry. Scotchbond Etchant (35% phosphoric acid gel) was applied to the occlusal fissures of each molar for 20 seconds. Fissures were then sealed as follows: Group 1: Concise Light Cured White Sealant was applied without vibration; Group 2: same as in Group 1 but with vibration; Group 3: Single Bond Adhesive was applied, then Concise Light Cured White Sealant was applied without vibration; Group 4: same as in Group 3, but sealant was applied with vibration; Group 5: Concise Light Cured White Sealant was applied without vibration, then Z-100 composite was burnished over the sealant and light-cured; Group 6: same as in Group 5, but sealant was applied with vibration. Microvibe vibrating probe was used for sealant vibration. After 24-hour immersion in 2% basic fuchsin dye solution, specimens were sectioned, and dye and sealant penetration were scored using a stereomicroscope and color slides. Selected sectioned samples were observed under the SEM. RESULTS: No statistically significant differences between the groups were observed for either dye or sealant penetration scores. In all groups, sealant penetration was more influenced by the shape, depth and residual debris of fissures than by the use of a vibrating probe.     

Comparison of blind and non-blind assessments of occlusal sealant retention

A comparison was made of scoring the retention status of BIS-GMA occlusal sealants 5 years after they had been placed, according to a non-blind and blind method of identification of teeth that had been sealed. Subjects were 175 children ages 15--18. One examiner made all the assessments. Retention of sealant was classified as all present, partly missing or all missing. There was 90.5% complete agreement between non-blind and blind examinations in scoring the retention status of 893 occlusal sites. Essentially no difference in agreement was found between sites on maxillary and mandibular teeth nor according to sites in specific teeth. There was only a slight tendency to classify more sites as having sealant present at the non-blind examinations than at the blind examinations, 56.7% and 55.1%, respectively. These findings would seem to indicate that whether examinations are done blindly or non-blindly is of minor importance in making an accurate assessment of sealant retention.